Rebuild

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AVOGTIR

Guest
evening all

i got bored this week, so i decided to do a freshen up, (head gasket bearings)

well it went from that to a total rebuild. :(

the piston crowns are in excellent condition, but the ringlands are a bit worn, so new pistons were ordered from rocket industries in Sydney, $661 + gst and $15 dollars delivery overnight bag.

they should turn up on monday.

also at some stage in it life it's been sized/spun bearing ect, so i am hoping the main journals are still straight otherwise, it's getting line bored :(

AND they changed the crank to a s14 one :(


anyways here are some pics of the motor with the head off.







matt
 
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jiw

Guest
Hi matt, looking good, if you where to line bore the block and mains caps id think twice, where would you get the oversize shells from? shells are only oversize on the bore not the o/d, not a dig just could end up costly, jeff :D
 
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AVOGTIR

Guest
i have spoen to the machine shop already about this, u nurl the block journals and main caps first then line bore... i am dreading it if it has to be done

matt
 
J

jiw

Guest
you wouldnt catch me knurling internal diameter's on mains caps, on a knurl you would gain a maximum of 0.016" and theirs no guarantee that it will be round therefore giving you an oval nip on your bearings, personally i wouldnt touch that machine shop with a barge pole as offering that kind of "BODGE" aint too safe and certainly aint profesional, and thats speaking with experience as ive worked as a machinist/fitter for six years, jeff
 
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AVOGTIR

Guest
we will see what happens.... hopefully it's all straight, i'll find out tomorrow
 
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MarkMc

Guest
When I got my engine rebuilt recently they line bored the block, but I’m sure they didn’t replace the crank. I think they also replaced the bearing with Nissom competition bearing. I don’t think they did any thing dogey either.
 
J

jiw

Guest
i dont think he is on about line boring the piston bores, i think he means the areas where the mains shells locate :?

if you go that route and you end up with an oval nip on the crank journal's that have been machined and knurled this will result in your engine siezing solid as the shell will no longer be able to just spin in its seat, this will then cost you that block you have just paid to have machined, the crank as it will probably be bent and damaged beyond repair, possibly pistons and rods, gaskets, time and patience, if the block is scrap id suggest you find a replacement, jeff
 
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AVOGTIR

Guest
it's only the no. 3 main jounrnal that is the concern, the bores will be machined that standard way, i thrust this guy, as he is the most honest guy i have met. . i will see what has to be said tomorrow., i think everything is ok, from my measurements. it' looked like there was a bit of shite on the back of the bearing, which may have cause it to shit wrong, plastic gauge will tell me if it is out..
 
M

MarkMc

Guest
jiw said:
i dont think he is on about line boring the piston bores, i think he means the areas where the mains shells locate :? jeff
Click to expand...
Just curious why would you only line bore the cylinders :?: I thought the whole idea was to make the crank spin true to bore.
 
A

Anonymous

Guest
AVOGTIR said:
it's only the no. 3 main jounrnal that is the concern, the bores will be machined that standard way, i thrust this guy, as he is the most honest guy i have met. . i will see what has to be said tomorrow., i think everything is ok, from my measurements. it' looked like there was a bit of sh**e on the back of the bearing, which may have cause it to s**t wrong, plastic gauge will tell me if it is out..
Click to expand...
number three hey.. haha. yeah i should get a photo of my number three for you, my bearing spun around and then came to a stop. was fused to the crank, and ripped the shit out of the number three journal..

wasnt up for repairing it. just bought a new block.
 
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AVOGTIR

Guest
well, i have just got back from machine shop, all good, the marks are the original machining marks, the journals are not honed, just machined to the finished size...

i dropped of the piston, now its a waiting game.
 
stevepudney

stevepudney

GTiROC CHAIRMAN
Staff member
Looking at those piston crowns it has defo been rebuilt before.

I've just finished a rebuild on my spare engine and when all the necessary bits went to the machine shop to be checked, bored & honed etc I was told the block needed line boring. Anyway it's common practice when line boring to take 0.005" off the bottom of all the main caps then without the bearings in place torque them all down to the specified amount then hone the main journals back to the original standard size. Everything will be perfectly round and true, no worries !!
 
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